# RUN: not llc -march=x86-64 -run-pass none -o /dev/null %s 2>&1 | FileCheck %s

--- |

  define zeroext i1 @t(i1 %c) {
  entry:
    ret i1 %c
  }

...
---
name:            t
tracksRegLiveness: true
registers:
  - { id: 0, class: gr32 }
  - { id: 1, class: gr8 }
  - { id: 2, class: gr8 }
body: |
  bb.0.entry:
    %0 = COPY $edi
    ; CHECK: [[@LINE+1]]:20: expected a subregister index after '.'
    %1 = COPY %0 . 42
    %2 = AND8ri %1, 1, implicit-def $eflags
    $al = COPY %2
    RET64 $al
...
